1. Field of the Invention
The present invention relates to a photosensitive belt removing device of an electrophotographic printing apparatus for removing a photosensitive belt from its installed position in order to replace the photosensitive belt installed in the electrophotographic printing apparatus, and a photosensitive belt removing method using the same.
2. Description of the Related Art
As shown in FIG. 1, an electrophotographic printing apparatus such as a color laser printer is provided with a photosensitive belt 10 which is supported by a plurality of rollers 11, 12 and 13 installed in a main body of the printing apparatus and circulates around a continuous loop. After an image to be printed is developed by predetermined developing units 15 on one surface of the photosensitive belt 10, and the developed image is dried while passing by a drying unit 16, the developed image is printed onto a paper 1 at a transfer unit 14 including a transfer roller 14a and a fuser roller 14b. 
In this case, a unit in which the photosensitive belt 10 is supported by rollers in a continuous loop shape and circulates around the continuous loop is called a belt unit. In the developing unit 15, reference numeral 15a denotes a developing roller for forming an image on the photosensitive belt 10 with developer liquid supplied from a developer liquid supply portion (not shown), and reference numeral 15b denotes a development backup roller. In addition, reference numerals 15c and 15d denote a squeeze roller and a squeeze backup roller for pressing the photosensitive belt 10 and squeezing surplus developer from an image developed by the developing roller 15a. 
However, when such a photosensitive belt 10 is used for a long time, the precision of an image deteriorates gradually. Therefore, when the photosensitive belt 10 reaches the end of its usable life, the photosensitive belt 10 must be replaced with a new one so that a clear image can be continuously developed. However, for such replacement, removal of a photosensitive belt 10 has been performed in a manner in which the used photosensitive belt 10 is taken out from its installed position in the belt unit directly by hand.
However, when, as described above, a user directly takes hold of and removes the photosensitive belt 10 after inserting his hand into a printer, the job in itself is bothersome and takes a long time, and, in addition, there is a danger in which the hand of the user may be injured due to interference with various structural frames when the photosensitive belt is taken out from the narrow inner space of the printer.
In addition, the printer is provided with a filter cartridge 17 therein for filtering internal air and exhausting the air. The filter cartridge 17 is arranged to filter foreign objects included in internal air while internal air passes through the filter cartridge 17 and is discharged to the outside by a discharge pump 18. Therefore, when the filter cartridge 17 is periodically replaced, and preferably replaced in accordance with the replacement period of the photosensitive belt 10, the filter cartridge 17 can maintain the required filtering capability.
However, in prior-art printers, since the filter cartridge 17 is handled separately from the photosensitive belt 10, it is troublesome to separately replace the filter cartridge 17 and the photosensitive belt 10 after they are separately removed.
To solve the above problems, it is an objective of the present invention to provide a photosensitive belt removing device of an electrophotographic printing apparatus which is adapted to perform the job of removing the photosensitive belt in a safe, convenient and fast manner, and a photosensitive belt removing method using the same.
Accordingly, to achieve the above objective, there is provided a photosensitive belt removing device of an electrophotographic printing apparatus for removing a photosensitive belt from its installed position in order to replace the photosensitive belt installed at a belt unit of the printing apparatus, the photosensitive belt removing device comprising: a belt cutting mechanism installed in the printing apparatus so as to cut in a widthwise direction the photosensitive belt installed at the belt unit in a continuous loop state; a filter cartridge installed in the vicinity of the belt unit for filtering objects floating in the air in the printing apparatus; an auxiliary housing provided at one side of the filter cartridge; a revolver rotatably installed in the auxiliary housing and provided with a through slot so that a leading edge of the photosensitive belt cut by the belt cutting mechanism can be inserted into the through slot; a leading edge introducing guide which guides the leading edge of the photosensitive belt cut by the belt cutting mechanism into the auxiliary housing and introduces the leading edge into the through slot of the revolver; and a driving source which rotates the revolver so that the revolver can wind up the photosensitive belt.
To achieve the above objective, there is provided a photosensitive belt removing method of an electrophotographic printing apparatus for removing a photosensitive belt from its installed position in order to replace the photosensitive belt installed at a belt unit of the printing apparatus, the printing apparatus including a photosensitive belt removing device, and the photosensitive belt removing device comprising a belt cutting mechanism installed in the printing apparatus so as to cut in a widthwise direction the photosensitive belt installed at the belt unit in a continuous loop state, a filter cartridge installed in the vicinity of the belt unit for filtering objects floating in the air in the printing apparatus, an auxiliary housing provided at one side of the filter cartridge, a revolver rotatably installed in the auxiliary housing and provided with a through slot so that a leading edge of the photosensitive belt cut by the belt cutting mechanism can be inserted into the through slot, a leading edge introducing guide which guides the leading edge of the photosensitive belt cut by the belt cutting mechanism into the auxiliary housing and introduces the leading edge into the through slot of the revolver, and a driving source which rotates the revolver so that the revolver can wind up the photosensitive belt, the photosensitive belt removing method including: cutting the photosensitive belt by operating the belt cutting mechanism; guiding the leading edge of the photosensitive belt cut by the belt cutting mechanism into the auxiliary housing and introducing the leading edge into the through slot of the revolver; winding the photosensitive belt into an auxiliary housing by rotating the revolver by the driving source; and taking the auxiliary housing into which the photosensitive belt is wound out of the printing apparatus together with the filter cartridge.